Please Help.2950s,2900XLs

Good Day

Our company has a problem. Would you be so kind to help us.

Here is a short description of our problem

Our clients have a network with the topology that described below. Two commutators 2900XL are connected by FEC and it is used 2/1-2/4(100FX). Commutators have IP-10.1.1.2 and IP-10.1.1.3 correspondingly. To each switchs (2900XL) is connected Cat2950s using by trunk connection (1/1-1/4100FX).The switches 2950 (10.1.1.4, 10.1.1.5, 10.1.1.6) are connected to the first switch with ip 10.1.1.2(2900XL) and the switches 2950(10.1.1.7,10.1.1.8,10.1.1.9) are connected to the second switch with ip 10.1.1.3(2900XL). . All commutators 2950 have 2950 IOS- 12.1(19)EA1a, and all commutators 2900XL have IOS-12.0(5)WC9. The switch 2900XL(10.1.1.2) are connected to the 2621 to achieve routing between VLANs.

There are four problems:

1). Ping from any 2950(10.1.1.4(5,6)) was successful and passed to the 2900XL(10.1.1.2). Ping command from 2950(10.1.1.4(5,6)) did not passed to the other 2950(10.1.1.4(5,6)) and 2900XL(10.1.1.3) which are connected to the 2900XL(10.1.1.2), till then 2900XL has not made Ping by itself to the switch. In other words commutators can make Ping command through 2900XL. After 3 or 5 minutes situation comes back.

3). At one of the 2950(10.1.1.7) big,very big , large and huge buffers have failures

4). On the both 2900XL at the loading procces have appeared mistake LINK-4-ERROR Fast1/1 is experiencing errors.. When we unplug this interface and make a reload we have the same problem on the next interface.

There are no redundant links in configuration. Speed and duplex on the trunk connection at the both side are tunned up in a similar manner. FEC is tunned up correctly. The type of topology is a star. The protocol CDP is switched off.

Please give your advise what is the problem? If this is the mistake of the equipment then what switch is wrong?

Re: Please Help.2950s,2900XLs

Answers according to your questions,

1. For this problem, I think 2900xl(10.1.1.2) is not forwarding first ARP packets of 2950 switches before ping packets to all ports i.e to connected 2900xl. Whenever, 2900xl pings itself to the other 2900xl and it's connected switches, then it's getting ARP reply and storing it in it's MAC address table. So that, as you said, after 3-5 min, that entry is getting aged out.

2. For this problem, a lot of choices, bad cable and security issues. Another option to check with "no keepalive" command on 2950 uplinks.

3). At one of the 2950(10.1.1.3) big,very big , large and huge buffers have failures

4). On the both 2900XL at the loading procces have appeared mistake LINK-4-ERROR Fast1/1 is experiencing errors.. When we unplug this interface and make a reload we have the same problem on the next interface.

2). All uplinks 2950 have ignored frames and broadcasting frames about 70-80 %. 10.1.1.11-has not ignoreds

3). At one of the 2950(10.1.1.3) big,very big , large and huge buffers have failures

4). On the both 2900XL at the loading procces have appeared mistake LINK-4-ERROR Fast1/1 is experiencing errors.. When we unplug this interface and make a reload we have the same problem on the next interface.

Re: Please Help.2950s,2900XLs

I have observed the problem and payed attention to the following thing. Such situation with ping happened only with VLAN 1 is not regular. Sometimes everything works ok. Maybe it's not connected with ARP tables?

In "show process cpu" on 2900XL (10.1.1.2,10.1.1.4) - BROADCAST STORM - 4%. How can it be (FEC has adjusted correct, STP is turn off(topology star)?)

Bad cables on all uplinks?

Device fault manager (CW2000) dose not show presence of any physical problems with switches.

This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
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Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
1. commandoversms.tcl
2. PDF with instructions on how to load and use the .tcl file.